Duramax Lifetime Supporter
Join Date: Oct 2016
Location: Maurice, LA
You don't need to bench bleed most master cylinders. Install it with the brake lines loose. Fill the reservoir. When bubbles stop coming out of the fittings, tighten them up.
Then go into the cab and depress the brake pedal about an inch many many times. Do this until bubbles stop appearing in the reservoir. That takes care of it in 99% of cases. If it doesn't then do the standard bleed with a helper depressing the pedal while you crack the bleeders.
A bit of effort to keep the brake lines from ingesting air goes a long way toward getting the brake pedal solid later.
As a final bleeding step you can compress the caliper pistons to push fluid back into the master cylinder and to push air out of the compensation ports in the reservoir.
Thanks, are there any check valves/springs in the MC that could keep pressure applied to the calipers after the brake pedal is released?
2008 Silverado 2500HD CCSB LTZ Diesel
FASS 95 Lift Pump (with Baldwin filters), Edge Insight CTS Monitor on a Windshield Mount, Nicktane Fuel Filter Adapter w/ CAT 306-9199 UHE tertiary fuel filter, Bilstein 5100 Stock Height, MBRP Downpipe back 4" exhaust with muffler and FTE 30" resonator/muffler, Sinister EGR Delete, Tuned but wont say who did it, Bushwacker Bed Rail Caps, AMP Research Bedstep, Fumoto oil drain valve, Dorman PS Oil cooler, Pioneer AVIC 7200NEX GPS/Stereo, Air Lift LoadLifter 5000 Air Bags.